Set Aside Unwanted ROMs by Keyword, Without Deleting Anything

<#
.SYNOPSIS
    Moves game files whose names contain unwanted keywords into a review folder, instead of deleting them.
.DESCRIPTION
    Checks every file name against a list of keywords, like "(Beta)", "(Proto)", "Mahjong" or "(Germany)", and moves
    each match into a review folder, keeping its subfolder path so you can put anything back where it came from.
    Keywords are matched as plain text, ignoring case. Use -WholeWord so "Pool" doesn't catch "Liverpool", or
    -Regex to write your own patterns. Files matching an -Except pattern are never moved (for example "[!]", the
    verified-dump flag).
    Nothing is deleted. Once you've looked through the review folder, deleting it is up to you.
    Every match gets an object back with the keyword that caught it. Supports -WhatIf.
.PARAMETER Path
    The folder to check.
.PARAMETER Keyword
    Keywords to look for. Combine with -KeywordFile or use either one.
.PARAMETER KeywordFile
    A text file with one keyword per line. Blank lines and lines starting with # are ignored.
.PARAMETER ReviewFolder
    Where matches go. Default: a "_review" folder inside -Path.
.PARAMETER Recurse
    Check subfolders too (the review folder itself is always skipped).
.PARAMETER Extension
    Only check these extensions. Default: every file.
.PARAMETER WholeWord
    Only match keywords as whole words.
.PARAMETER Regex
    Treat keywords as regular expressions.
.PARAMETER Except
    Regular expressions for names that must never be moved.
.EXAMPLE
    .\Move-RomByKeyword.ps1 -Path D:\Games\snes -Keyword '(Beta)','(Proto)','(Demo)' -WhatIf
.EXAMPLE
    .\Move-RomByKeyword.ps1 -Path D:\Games -Recurse -KeywordFile .\skip-list.txt -WholeWord -Except '\[!\]' | Export-Csv moved.csv -NoTypeInformation
#>
[CmdletBinding(SupportsShouldProcess)]
param(
    [Parameter(Mandatory)]
    [ValidateScript({ Test-Path -LiteralPath $_ -PathType Container })]
    [string]$Path,

    [string[]]$Keyword,

    [ValidateScript({ Test-Path -LiteralPath $_ -PathType Leaf })]
    [string]$KeywordFile,

    [string]$ReviewFolder,
    [switch]$Recurse,
    [string[]]$Extension,
    [switch]$WholeWord,
    [switch]$Regex,
    [string[]]$Except
)

$root = (Resolve-Path -LiteralPath $Path).ProviderPath.TrimEnd('\', '/')
if (-not $ReviewFolder) { $ReviewFolder = Join-Path $root '_review' }
$reviewFull = [System.IO.Path]::GetFullPath($ReviewFolder).TrimEnd('\', '/')

$words = @($Keyword | Where-Object { $_ })
if ($KeywordFile) { $words += Get-Content -LiteralPath $KeywordFile | ForEach-Object { $_.Trim() } | Where-Object { $_ -and -not $_.StartsWith('#') } }
if (-not $words.Count) { throw 'Give at least one keyword with -Keyword or -KeywordFile.' }

$patterns = foreach ($w in $words) {
    $p = if ($Regex) { $w } else { [regex]::Escape($w) }
    if ($WholeWord) { $p = "(?<![A-Za-z0-9])$p(?![A-Za-z0-9])" }
    try { [pscustomobject]@{ Keyword = $w; Re = [regex]::new($p, 'IgnoreCase') } }
    catch { Write-Warning "Skipping keyword '$w': not a valid pattern." }
}

$extFilter = @($Extension | Where-Object { $_ } | ForEach-Object { if ($_ -like '.*') { $_.ToLower() } else { ".$_".ToLower() } })
$files = Get-ChildItem -LiteralPath $root -File -Recurse:$Recurse | Where-Object {
    (-not $extFilter -or $extFilter -contains $_.Extension.ToLower()) -and
    -not $_.FullName.StartsWith($reviewFull + [System.IO.Path]::DirectorySeparatorChar, [StringComparison]::OrdinalIgnoreCase)
}

foreach ($file in $files) {
    if (@($Except | Where-Object { $_ -and $file.Name -match $_ }).Count) { continue }
    $hit = $patterns | Where-Object { $_.Re.IsMatch($file.Name) } | Select-Object -First 1
    if (-not $hit) { continue }

    $relative = $file.FullName.Substring($root.Length).TrimStart('\', '/')
    $dest = Join-Path $reviewFull $relative
    $result = [ordered]@{ Name = $file.Name; Keyword = $hit.Keyword; From = $file.DirectoryName; To = (Split-Path $dest -Parent); Status = 'WhatIf' }

    if (Test-Path -LiteralPath $dest) {
        $result.Status = 'SkippedExists'
        Write-Warning "$relative is already in the review folder. Left alone."
        [pscustomobject]$result; continue
    }

    if ($PSCmdlet.ShouldProcess($file.FullName, "Move to review folder (matched '$($hit.Keyword)')")) {
        try {
            $destDir = Split-Path $dest -Parent
            if (-not (Test-Path -LiteralPath $destDir)) { New-Item -ItemType Directory -Path $destDir -ErrorAction Stop | Out-Null }
            Move-Item -LiteralPath $file.FullName -Destination $dest -ErrorAction Stop
            $result.Status = 'Moved'
        }
        catch {
            $result.Status = "Failed: $($_.Exception.Message)"
            Write-Warning "$($file.Name): $($_.Exception.Message)"
        }
    }
    [pscustomobject]$result
}